1-21876583-C-T

Position:

• chr1-21876583-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 1P and 0B. PP2

The NM_005529.7(HSPG2):​c.2755G>A​(p.Asp919Asn) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000821 in 1,461,866 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. D919E) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000082 (0 hom.)
• Consequence: HSPG2 NM_005529.7 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 2.91

Genes affected

HSPG2 (HGNC:5273): (heparan sulfate proteoglycan 2) This gene encodes the perlecan protein, which consists of a core protein to which three long chains of glycosaminoglycans (heparan sulfate or chondroitin sulfate) are attached. The perlecan protein is a large multidomain proteoglycan that binds to and cross-links many extracellular matrix components and cell-surface molecules. It has been shown that this protein interacts with laminin, prolargin, collagen type IV, FGFBP1, FBLN2, FGF7 and transthyretin, etc., and it plays essential roles in multiple biological activities. Perlecan is a key component of the vascular extracellular matrix, where it helps to maintain the endothelial barrier function. It is a potent inhibitor of smooth muscle cell proliferation and is thus thought to help maintain vascular homeostasis. It can also promote growth factor (e.g., FGF2) activity and thus stimulate endothelial growth and re-generation. It is a major component of basement membranes, where it is involved in the stabilization of other molecules as well as being involved with glomerular permeability to macromolecules and cell adhesion. Mutations in this gene cause Schwartz-Jampel syndrome type 1, Silverman-Handmaker type of dyssegmental dysplasia, and tardive dyskinesia. Alternative splicing of this gene results in multiple transcript variants. [provided by RefSeq, May 2014]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), HSPG2. . Gene score misZ 1.1367 (greater than the threshold 3.09). Trascript score misZ 3.3999 (greater than threshold 3.09). GenCC has associacion of gene with Silverman-Handmaker type dyssegmental dysplasia, Schwartz-Jampel syndrome type 1, Schwartz-Jampel syndrome.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
HSPG2	NM_005529.7	c.2755G>A	p.Asp919Asn	missense_variant	22/97	ENST00000374695.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
HSPG2	ENST00000374695.8	c.2755G>A	p.Asp919Asn	missense_variant	22/97	1	NM_005529.7	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251288 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135852

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000821 AC: 12 AN: 1461866 Hom.: 0 Cov.: 33 AF XY: 0.00000688 AC XY: 5 AN XY: 727230

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000989

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 33

ExAC AF: 0.0000165 AC: 2

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Athena Diagnostics

Sep 26, 2016

- -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Revvity Omics, Revvity

May 23, 2019

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.093
BayesDel_addAF	Benign	-0.17	T
BayesDel_noAF	Benign	-0.49
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Benign	0.33	T
Eigen	Uncertain	0.42
Eigen_PC	Uncertain	0.35
FATHMM_MKL	Uncertain	0.81	D
LIST_S2	Uncertain	0.95	D
M_CAP	Benign	0.035	D
MetaRNN	Uncertain	0.49	T
MetaSVM	Benign	-0.71	T
MutationAssessor	Benign	1.6	L
MutationTaster	Benign	0.99	N
PrimateAI	Uncertain	0.50	T
PROVEAN	Benign	-2.3	N
REVEL	Benign	0.16
Sift	Benign	0.073	T
Sift4G	Uncertain	0.0080	D
Polyphen		1.0	D
Vest4		0.34
MutPred		0.41		Loss of ubiquitination at K923 (P = 0.0343);
MVP		0.59
MPC		0.72
ClinPred		0.84	D
GERP RS		3.9
Varity_R		0.095
gMVP		0.39

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs752051085; hg19: chr1-22203076;